How do I try b43.allhwsupport=1?

The message that I get upon bootup says…

[35.615862] Support for cores revisions 0x17 and 0x18 disabled by module param allhwsupport=0. Try b43.allhwsupport=1

More information would be helpful. I’m assuming you manually installed the legacy b43 driver and firmware?

Module parameters can be added like this in /etc/modprobe.d or at boot using the kernel boot commandline (see man clr-boot-manager)